Assembly for attaching fabric to metal and method of fabrication therefor

ABSTRACT

A product having a metal-fabric joint includes forming a fabric anchoring component by casting a low melting point yet high compressive strength material into a cavity in a metal component. The product includes (a) a metal housing including an interior entrance, at least first and second opposed interior walls, and an interior end opposite the interior entrance, the at least first and second opposed interior walls and the interior end defining an interior cavity; (b) a fabric; (c) a fabric anchor assembly; and (d) a castable material disposed in the interior cavity so as to envelop the fabric and the fabric anchor assembly. A method of fabricating the product includes the steps of (a) anchoring the fabric with the fabric anchor assembly; (b) inserting the anchored fabric in the interior cavity; (c) providing the interior cavity with the castable material so as to envelop the anchored fabric; and (d) solidifying the castable material to a cast material so as to form the product. Advantages associated with the product include not only its simplicity, compact size, and light weight, but the requisite mechanical integrity of the resulting attachment. In addition, by using a low melting point material for the castable material in some embodiments, the product can be easily disassembled for repair or replacement of components by simply melting the castable material out of the interior cavity.

This application is a continuation of U.S. application Ser. No.09/589,771, filed Jun. 9, 2000, now U.S. Pat. No. 6,612,360, whichclaims the priority of U.S. Provisional Application No. 60/138,536 filedJun. 10, 1999, and incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to a method of and apparatus forattaching a fabric component to a metal component. The invention relatesmore specifically to a means for anchoring the fabric component bycasting a low melting point yet high compressive strength material intoa cavity in the metal component.

2. Description of Related Art

In the design of full pressure suits such as space suits, fabriccomponents have traditionally been attached to metal components (e.g.,bearings, sizing rings, and transition sections) by capturing the fabricunder a flange mounted retainer ring using machine screws and seals,such as the conventional technique depicted in FIG. 1.

The fabric component 10 is fabricated with a mounting flange 20terminating in a “deadman” 30 so as to prevent material pullout. Boltholes 21 are located and punched in the metal mounting flange 20. Ametal clamping ring 40 is fabricated with the same hole pattern 41 asthat of the flange. In addition, an O-ring seal groove 22 is machined toaccommodate O-ring seal 23. The fabric component 10 is then flangemounted to the metal component 20 by means of the bolts 50.

Disadvantages associated with the conventional technique, however,include both the amount of space occupied by the flange section, and theweight of the overall assembly.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a means forattaching a fabric component to a metal component which is bothrelatively compact and lightweight, yet which also provides therequisite secure attachment between the components.

Accordingly, in a first preferred embodiment the present inventionadvantageously relates to a means for anchoring the fabric component bycasting a low melting point yet high compressive strength material intoa cavity in the metal component.

In a typical embodiment, the assembly for attaching fabric to metalcomprises (a) a metal housing comprising an interior entrance, at leastfirst and second opposed interior walls, and an interior end oppositethe interior entrance, the at least first and second opposed interiorwalls and the interior end defining an interior cavity; (b) a fabric;(c) a fabric anchor assembly; and (d) a castable material disposed inthe interior cavity so as to envelop the fabric and the fabric anchorassembly.

More specifically, the assembly for attaching comprises a metal housingcomprising an undercut, e.g., a dovetail-shaped, cavity at thefabric/metal attachment interface, fabric, anchor, stitching, andcastable material.

In a second preferred embodiment of the assembly for attaching, thewalls of the cavity are coated with a rigid thermoplastic adhesive so asto provide for adhesion of the castable material to the walls.

In a third preferred embodiment of the assembly for attaching, aflexible sealant is disposed in a portion of cavity between the castablematerial and a first end of the cavity. This flexible sealant serves asa transition section to reduce the stress concentration of the fabric atthe fabric/metal interface.

In a fourth preferred embodiment of the assembly for attaching, abladder layer is disposed so as to be contiguous with the fabriccomponent.

The invention further relates to a method of fabricating theaforementioned assembly for attaching fabric to metal. In a typicalembodiment, the method comprises the steps of (a) anchoring the fabricwith the fabric anchor assembly; (b) inserting the anchored fabric inthe interior cavity; (c) providing the interior cavity with the castablematerial so as to envelop the anchored fabric; and (d) solidifying thecastable material to a cast material so as to provide the assembly forattaching.

Advantages associated with the assembly for attaching include not onlyits simplicity, compact size, and light weight, but the requisitemechanical integrity of the resulting attachment. In addition, by usinga low melting point material for the castable material, the assembly canbe easily disassembled for repair or replacement of components by simplymelting the castable material out of the interior cavity.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features, and advantages of the present invention willbecome more fully apparent from the following detailed description ofthe preferred embodiments and the accompanying drawings. As depicted inthe attached drawings:

FIG. 1 is an exploded sectional view of a prior art means for attachinga fabric component to a metal component.

FIG. 2 is a sectional view of an assembly for attaching a fabriccomponent to a metal component according to a first preferred embodimentof the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will be disclosed in terms of the currentlyperceived preferred embodiments thereof.

The present invention provides a means for attaching a fabric componentto a metal component which is both relatively compact and lightweight,yet which also provides the requisite secure attachment between thecomponents.

Accordingly, in a first preferred embodiment the present inventionadvantageously relates to a means for anchoring the fabric component bycasting a low melting point yet high compressive strength material intoa cavity in the metal component.

Referring to FIG. 2, in the first preferred embodiment, the assembly 110for attaching fabric to metal comprises (a) a metal housing 120comprising an interior entrance 121, at least first and second opposedinterior walls 122, and an interior end 123 opposite the interiorentrance 121, the at least first and second opposed interior walls 122and the interior end 123 defining an interior cavity; (b) a fabric 130;(c) a fabric anchor assembly 140; and (d) a castable material 150disposed in the interior cavity so as to envelop the fabric 130 and thefabric anchor assembly 140.

In a typical embodiment, fabric 130 comprises a first fabric portion 131and a second fabric portion 132, and fabric anchor assembly 140comprises an anchor 141 and a means for attaching fabric 130 to anchor141, such as, for example, stitching 142. Anchor 141 is preferably of aconstruction which does not contain voids (which can lead to compressionof the anchor), and therefore is typically a monofilament, a cable, or awire.

More specifically, again referring to FIG. 2, in a typical embodimentthe attachment assembly 110 comprises a metal housing 120 comprising anundercut, e.g., a dovetail-shaped, cavity at the fabric/metal attachmentinterface (i.e., that portion of the assembly adjacent to interiorentrance 121), fabric 130 comprising first fabric portion 131 and secondfabric portion 132, anchor 141, stitching 142, and castable material150.

Castable material 150 is a high compressive strength material. Polymericmaterials, including both thermoplastic and thermosetting types, aresuitable for use as the castable material. In a service in which thepossibility of disassembly of the components is desired, the materialshould typically be one which has a relatively low melting point, e.g.,thermoplastic polymeric materials and low melting point metal alloys.For example, the thermoplastic polymeric material could be a hot meltadhesive, and the low melting point metal alloy could be a low meltingpoint solder alloy. Such thermoplastic polymeric materials and lowmelting point metal alloys are preferred insofar as they can be easilyremoved to facilitate disassembly of the components.

By using such a low melting point material for the castable material,assembly 110 can be easily disassembled for repair or replacement ofcomponents by simply melting castable material 150 out of the interiorcavity.

Optionally, in a service in which a permanent attachment is desired, thefabric and fabric anchor assembly can be locked in place by filling theinterior cavity with a thermoset material, such as, for example, anepoxy.

In a second preferred embodiment of the assembly for attaching, theassembly further comprises a coating of rigidized thermoplastic adhesivedisposed on each of first and second opposed interior walls 122 of metalhousing 120. Walls 122 are coated with a rigid thermoplastic adhesivecompatible with the hot melt adhesive and/or low melting point solderalloy so as to provide for adhesion of castable material 150 to thewalls 122. This embodiment provides for a level of structural andleakage integrity even beyond that afforded by the mechanical lockingaction of the castable material in the cavity.

In a third preferred embodiment of the assembly for attaching, theassembly further comprises a flexible sealant 160 disposed in a portionof the interior cavity located between castable material 150 andinterior entrance 121. This flexible sealant serves as a transitionsection to reduce the stress concentration of the fabric at thefabric/metal interface.

In a fourth preferred embodiment of the assembly for attaching, theassembly further comprises a bladder layer disposed so as to becontiguous with fabric 130. The bladder layer thus contacts the hot meltadhesive and/or low melting point solder alloy so as to improveadhesion.

The invention further relates to a method of fabricating assembly 110for attaching fabric to metal. In a first preferred embodiment, themethod comprises the steps of (a) anchoring fabric 130 with fabricanchor assembly 140; (b) inserting the anchored fabric in the interiorcavity; (c) providing the interior cavity with the castable material 150so as to envelop the anchored fabric; and (d) solidifying the castablematerial to a cast material so as to provide the assembly 110.

In a typical embodiment, the method of fabricating assembly 110comprises the steps of (a) folding first fabric portion 131 over anchor141, and folding folded first fabric portion 131 back against secondfabric portion 132; (b) attaching folded first fabric portion 131 tosecond fabric portion 132 with the means for attaching so as to providean anchored fabric; (c) inserting the anchored fabric in the interiorcavity; (d) providing the interior cavity with castable material 150 soas to envelop the anchored fabric; and (e) solidifying castable material150 to a cast material so as to provide assembly 110.

More specifically, again referring to FIG. 2, preliminarily an undercutinterior cavity, e.g., a dovetail-shaped cavity having a first end and asecond end is provided in metal housing 120 by a method such asmachining. The cross section of the cavity can be made to follow thecontour of the fabric/metal interface (e.g., circular, cylindrical, orany other desired shape).

Next, fabric anchor assembly 140 (sometimes generically referred to as a“deadman”) is fabricated by folding first fabric portion 131 of fabric130 over anchor 141 (which is, typically, the aforementionedmonofilament, cable, or wire), and then folding first fabric portion 131back against second fabric portion 132. First fabric portion 131 andsecond fabric portion 132 are then attached to one another by a suitablemeans for attaching, such as, for example, stitching 142.

To facilitate the insertion of fabric anchor assembly 140 into theinterior cavity, interior entrance 121 of metal housing 120 has a widththat is slightly larger than the diameter of fabric anchor assembly 140.

Once fabric 130 and fabric anchor assembly 140 (i.e., the “anchoredfabric”) have been placed in the portion of the cavity generallyadjacent to interior end 123, castable material 150 is provided withinthe cavity so as to envelop fabric 130 and fabric anchor assembly 140.Castable material 150 is then solidified to form a cast material, so asto mechanically lock fabric 130 and fabric anchor assembly 140 in place,and thus provide assembly 110.

In a second embodiment of the method of fabricating the assembly forattaching, the method further comprises after step (a) and before step(b) a step of providing a coating of rigidizable thermoplastic adhesivedisposed on each of the first and second opposed interior walls 122.

In a third embodiment of the method of fabricating the assembly forattaching, the method further comprises after step (c) and before step(d) a step of providing a flexible sealant 160 disposed in a portion ofthe interior cavity located between castable material 150 and interiorentrance 121.

In a fourth embodiment of the method of fabricating the assembly forattaching, the method further comprises after step (b) and before step(c) a step of providing a bladder layer disposed so as to be contiguouswith the fabric 130.

The present invention, therefore, provides a means for anchoring afabric component by casting a low melting point yet high compressivestrength material into a cavity in a metal component. Advantagesassociated with the invention include not only its compact size andlight weight, but the requisite mechanical integrity of the resultingattachment. In addition, by using a low melting point material for thecastable material, the assembly can be easily disassembled for repair orreplacement of components by simply melting the castable material out ofthe interior cavity.

While only certain preferred embodiments of this invention have beenshown and described by way of illustration, many modifications willoccur to those skilled in the art. For example, while the attachmentassembly has been described in one embodiment in the context of apressure suit application, its use is equally applicable to any servicewhich requires a secure but relatively compact and lightweightattachment between fabric and metal components.

By way of further example of modifications within the scope of thisinvention, while the cavity has been described in a first preferredembodiment as being dovetail-shaped, another embodiment could compriseany geometry which provides both the requisite access to the anchoringmeans and the mechanical locking of the castable material.

By way of further example of modifications within the scope of thisinvention, while the assembly for attaching has been described in afirst preferred embodiment as comprising a single fabric and a singlefabric anchor assembly, another embodiment could comprise a plurality offabrics (i.e., a plurality of fabric layers) and a correspondingplurality of fabric anchor assemblies (i.e., a separate anchor dedicatedto each fabric layer), all contained within a single interior cavity. Byvirtue of the ability to easily disassemble the assembly by simplymelting the castable material out of the interior cavity, a particularlayer of fabric could be easily removed for repair or replacement.

It is, therefore, desired that it be understood that it is intendedherein to cover all such modifications that fall within the true spiritand scope of this invention.

1. A product comprising a metal-fabric joint, said joint comprising: (a)a metal housing comprising an interior entrance, at least first andsecond opposed interior walls, and an interior end opposite saidinterior entrance, said at least first and second opposed interior wallsand said interior end defining an interior cavity; (b) a fabriccomprising a first fabric portion and a second fabric portion; (c) afabric anchor assembly comprising an anchor and a means for attachingsaid fabric to said anchor, such that said fabric is at least partiallydisposed inside said interior cavity, and said first fabric portion isfolded over said anchor; and (d) a low melting point, high compressivestrength, castable material disposed in said interior cavity so as toenvelop said fabric at least partially disposed inside said interiorcavity and said fabric anchor assembly, wherein said castable materialis selected from the group consisting of a thermoplastic polymer and alow melting point metal alloy.
 2. A product comprising a metal-fabricjoint, said joint comprising: (a) a metal housing comprising an interiorentrance, at least first and second opposed interior walls, and aninterior end opposite said interior entrance, said at least first andsecond opposed interior walls and said interior end defining a cavity;(b) a plurality of fabric layers; (c) a plurality of fabric anchorassemblies corresponding in number to said plurality of fabric layers,wherein each of said plurality of fabric layers have a dedicated fabricanchor assembly, and at least one of said plurality of fabric layers isfolded over its dedicated fabric anchor assembly; and (d) a castablematerial disposed in said interior cavity so as to envelop saidplurality of fabric layers and said plurality of fabric anchorassemblies.
 3. A product comprising a metal-fabric joints, said jointcomprising: (a) a metal housing comprising an interior entrance, atleast first and second opposed interior walls, and an interior endopposite said interior entrance, said at least first and second opposedinterior walls and said interior end defining a cavity; (b) a fabric;(c) a fabric anchor assembly; (d) a thermoset material disposed in saidinterior cavity so as to envelop said fabric and said fabric anchorassembly.
 4. The product of claim 3, wherein said thermoset comprises atleast one member selected from the group consisting of hot meltadhesives and epoxies.
 5. A product comprising a metal-fabric joint,said joint comprising: (a) a metal housing comprising an interiorentrance, at least first and second opposed interior walls, and aninterior end opposite said interior entrance, said at least first andsecond opposed interior walls and said interior end defining an interiorcavity, wherein said interior end of the metal housing is wider thansaid interior entrance of the metal housing; (b) a fabric; (c) a fabricanchor assembly comprising a portion of said fabric and an anchor, saidanchor assembly being located inside said interior cavity, such thatsaid portion of said fabric is positioned inside said interior cavity;and (d) a castable material disposed in said interior cavity so as toenvelop said portion of said fabric and said fabric anchor assembly,wherein said castable material is selected from the group consisting ofa thermoset material and a low melting point metal alloy.
 6. The productof claim 5, wherein the castable material is a low melting point metalalloy.
 7. The product of claim 5, further comprising a rigidizedthermoplastic adhesive on the interior walls of the housing.
 8. Theproduct of claim 5, further comprising a flexible sealant between thecastable material and interior entrance.
 9. The product of claim 5,wherein the fabric comprises a bladder layer, contiguous with thefabric.
 10. The product of claim 5, wherein the fabric anchor assemblycomprises at least one selected from the group consisting of amonofilament, a cable and a wire.
 11. The product of claim 5, wherein afirst portion of the fabric is folded over the anchor, and the foldedfirst fabric portion is folded back against a second fabric portion and,the folded first fabric portion is attached to the second fabricportion.
 12. The product of claim 5, wherein the fabric comprises aplurality of fabric layers and the anchor comprises a plurality ofanchor members, wherein the number of anchor members is equal to thenumber of fabric layers.
 13. A metal-fabric joint comprising (i) a metalhousing comprising an interior entrance, at least first and secondopposed interior walls, and an interior end opposite said interiorentrance, said at least first and second opposed interior walls and saidinterior end defining an interior cavity; (ii) a fabric comprising afirst fabric portion and a second fabric portion; (iii) a fabric anchorassembly comprising an anchor and a means for attaching said fabric tosaid anchor; and (iv) a castable material disposed in said interiorcavity, wherein said castable material is selected from the groupconsisting of a thermoplastic polymer and a low melting point metalalloy, formed by a method comprising the steps of: (a) folding saidfirst fabric portion over said anchor, and folding said folded firstfabric portion back against said second fabric portion; (b) attachingsaid folded first fabric portion to said second fabric portion with saidmeans for attaching so as to provide an anchored fabric; (c) insertingsaid anchored fabric in said interior cavity, whereby said first fabricportion is positioned inside said interior cavity; (d) providing saidinterior cavity with said castable material so as to envelop saidanchored fabric; and (e) solidifying said castable material to form acast material so as to provide said metal-fabric joint.
 14. Ametal-fabric joint comprising (i) a metal housing comprising an interiorentrance, at least first and second opposed interior walls, and aninterior end opposite said interior entrance, said at least first andsecond opposed interior walls and said interior end defining an interiorcavity; wherein the interior end of the metal housing is wider than theinterior entrance of the metal housing; (ii) a fabric comprising a firstfabric portion and a second fabric portion; (iii) a fabric anchorassembly comprising an anchor and a means for attaching said fabric tosaid anchor; and (iv) a castable material disposed in said interiorcavity, formed by a method comprising the steps of: (a) folding saidfirst fabric portion over said anchor, and folding said folded firstfabric portion back against said second fabric portion; (b) attachingsaid folded first fabric portion to said second fabric portion with saidmeans for attaching so as to provide an anchored fabric; (c) insertingsaid anchored fabric in said interior cavity, whereby said first fabricportion is positioned inside said interior cavity; (d) providing saidinterior cavity with said castable material so as to envelop saidanchored fabric; and (e) solidifying said castable material to a castmaterial so as to provide said metal-fabric joint.